Electricity Saving Tips For Homes And Offices

Split or Window … which air conditioner should you buy?

By on July 29, 2015

Hindi Translation: स्प्लिट और विंडो - कौन सा एयर कंडीशनर खरीदना चाहिए?

Should I buy a split air conditioner or a window air conditioner? This is a question that many air conditioner buyers thinks of, before making a purchase. And we keep getting this question quite regularly at Bijli Bachao. It is not just about split or window, but about a whole lot of things that should be considered while buying an air conditioner.  Air Conditioner is an appliance that can significantly blow up your electricity bills and utmost care should be taken while buying one. With this article we would try to provide you some guidelines on things to take care of before making a purchase decision for an air conditioner. Please note an air conditioner bought once will go on for next 10 years at least and thus it is important to make a right decision.

Air Conditioner

Split vs Window

Buying a split or a window is something that worries a lot of people. But from energy efficiency perspective there is no preferred choice. Both split and window can be equally efficient. What matters is EER or Energy Efficiency Ratio of the air conditioner. EER represents the amount of cooling an air conditioner can provide per watt of electricity it consumes. Bureau of Energy Efficiency rates air conditioners on its star rating based on EER of air conditioners. Higher the EER of air conditioner higher the star rating it will have. So a 5 star rated air conditioner provides more cooling per watt of electricity used.

Both split and window can have high EER ratios. But it is observed that Split air conditioners have more number of models in BEE 5 star rating as compared to Window air conditioners (check our research on air conditioners at this link: link). So if you are looking for high efficiency air conditioners then split air conditioners can provide you more options.

The main difference between the two is that window air conditioner has a single unit whereas split air conditioner has 2 units (indoor and outdoor). Split is lot more silent in operation as compared to window and looks aesthetically pleasing, but is relatively more complicated to install and requires more space as compared to window air conditioner.

Right sizing an air conditioner is very important

The most important thing that one should figure out before buying any air conditioner is the right size of the air conditioner. This can significantly impact your electricity bills. And from size we mean tonnage of air conditioner. Every room that is cooled has a certain amount of heat that depends on:

  1. Size of the room. This determines the amount of air in the room that needs to be cooled.
  2. Number of people in the room. Every human being emits heat and air conditioner needs to cool it.
  3. Amount of stuff kept in the room. Please note every item kept in the room will get cooled from the air conditioner, so lesser the stuff, lesser the electricity air conditioner will consume.
  4. Number of electrical appliances in the room (most electrical appliances emit heat, especially lights). Incandescent light bulbs can increase cooling load.
  5. Windows in the room. More the windows, more is the heat coming from outside. Well-insulated windows reduce cooling load. Check our insulation section for more details: https://www.bijlibachao.com/Save-Electricity/Insulation/
  6. Walls facing the sun can increase cooling load. Touch your walls and windows to check if they are hot or not and using the tips in insulation section to prevent heating of the room.

The amount of heat in a room and that coming in from walls and windows is represented in BTU (or British Thermal Unit). BTU is sum of heat from all the above-mentioned sources.

Every air conditioner has a cooling capacity, which is represented in BTU/hr. It is the BTUs of heat that it can remove in an hour. If the heat coming in the room (in BTUs) is more than the heat that air conditioner can remove, then the air conditioner will not be as effective. Thus an undersized air conditioner cannot remove heat effectively and the compressor of the air conditioner will continue running all the time thereby consuming more electricity.

With an undersized air conditioner, the compressor will keep running all the time and the temperature will not reach the desired level. They will not only be ineffective in cooling, but will also consume more electricity.

An oversized air conditioner will not only over cool your room but also will be ineffective in removing the humidity in a room. So if you set AC to 25, the extra energy that the compressor provides will cool it beyond 25. It will have shorter run cycles but all air conditioners are designed for optimum run cycles and if the cycle is shorter than that then the efficiency is reduced (source: energy star).

So every air conditioner is designed to run at optimum efficiency only if it is used as per the right size. So always size the air conditioner properly. You can use the calculator available at this link before buying an air conditioner: http://www.lg.com/in/support/ac-tonnage-calculator.

If you are not sure about what size to buy, you can always buy an inverter technology air conditioner, as it adjusts to the size and requirements of the room automatically, and thus makes optimum electricity consumption. To check more about inverter ac see our article: Air Conditioners with Inverter technology can help save electricity.

Look for the right options in the air conditioner

In a previous article (Various modes for running air conditioners and their impact on electricity bill) we discussed about various modes of air conditioners and their impact on electricity consumption. It is very important to figure out if the air conditioner has all the modes as per your requirement. If you live in humid area, a dry mode is important. Any air conditioner with energy saver mode and features should be preferred.

Star rating is for real

BEE Star rating of air conditioner does matter a lot. Any air conditioner would consume anywhere between 1-2 units per hour of usage based on tonnage, efficiency and size. Which means if it is used for 10 hours per day, it can consume about 10-20 units in a day or 300-600 units a month (for 10 hours of use daily). At an average rate of Rs 6-7 per unit (you can check your per unit rate using our calculator: Online Electricity Bill Calculator – For all states in India) it can be close to Rs 1800-4000 per month. If your usage is high then the yearly cost of an air conditioner can go very high. In case of high usage, incremental cost of buying a higher star rated air conditioner can easily be recovered in a few years. Please note that the air conditioner will work for at least 10 years and the electricity prices are on a rise. Buying an efficient one while buying a new air conditioner can prevent a lot of heartburn for you in future.

It is important to make a right decision while buying an air conditioner, as it is a long-term utility for you. Do not let lucrative deals, discounts and persuasion by a sales person impact your decision to buy an efficient appliance. A wrong decision on an appliance like air conditioner can significantly impact your electricity bills. We are trying to work out a calculator that can help you choose the right air conditioner for you and hope to release it soon. Till that time you can check the list of top ten most efficient air conditioners at: Top Ten Air Conditioners in India by electricity consumption and size.

Here is a short video for tips to buy the best air conditioner in India

Check this link to see Top Ten Air Conditioners in India for Electricity Savings: http://wp.me/p4hAhQ-4I





Leave a Reply

230 Comments on "Split or Window … which air conditioner should you buy?"

If you have any question or comment, please leave a message here. We try to reply to questions in the sequence they come in. We work from Monday-Friday 10AM-7PM. If we know the answer we try to reply to the question within 3 days.

Rahul Haldar
July 26, 2015

Respected Team Bijli Bachao,

I Am From Kolkata And My Room Size Is 11 By 11. I Have Installed A Panasonic 1 Tonn Split Air Conditioner 2 Months Back And Has Set The Temperature To 27 In Cool Mode And It Get Used For Around 12 to 16 Hours A Day.. My Electricity Bill Is Now Coming Somewhere Around Rs. 1500 Per Month. Is It Appropriate???

Rashpal Singh
July 20, 2015

Sir for my 12′ x 13′ room at ground floor with only south side wall exposed to sunlight , is one ton inverter ac is sufficient , because at start it almost run on about 1400 watt (which is equal to 1.5 ton ac) then gradually going down to 1000 watt and more lower. please advice me. i am going for carrier superia 365 brand

July 20, 2015

sir i live in jalandhar punjab

July 14, 2015

Hi my name is Naresh planning to buy a A.C first time . My room size is 10*9. So i am just confuse which A.C I should buy either split AC or Window Ac. I have window also in my room. So please suggest me sir which one I should buy and also the power consumption ?

July 16, 2015

I stay in Secuderabad , and my house in ground floor and in my room has one window is there. And my room size is length-12” and breadth 13”. Mostly I use in summer why because on summer it causes more heat in our room. So please suggest us a good AC either window or Split with power consumption as I am a normal family member.

June 29, 2015

Want to buy only window ac(1.5ton) with best EER.cant dig holes in my landlords wall.can u please suggest me

June 27, 2015

The biggest point seems left out between Window and Split Ac is its maintenance especially of the Out door unit / Condenser Unit in a split which is prone to nuisance from birds & cats and even insects. The insulation widely used for insulating the copper tubes are of such inferior quality that within a few months of the first summer it is damaged. The insulation tube is required to be EPDM rubber which is strong and does not get affected by rain or shine.
If the tubes get heated up or damaged the very functioning of the split AC is badly affected leading to expensive repairs.
The installation is outsourced. 99.99% of these installation guys are most unreliable and unscrupulous. They use very cheap to cheap quality of copper tubes and insulation materials thus leading to lot of troubles in the medium run.

July 3, 2015

Thanks for appreciating the points raised by me. It is noteworthy that the installers use substandard and low quality insulation material. The copper tubes used are often inferior quality. The thickness is dubious so much so they even get punctured easily even during installation. All these have a STRONG BEARING on the power consumption.

June 24, 2015

Can you please suggest which A/C is of low maintenance. I understand O’G or Daikin are good. Is it so?

June 24, 2015

Yes true. I actually had a Voltas AC for last 4 years and had spent almost the AC cost on service/maintenance. So I am really looking for some ac which will stand good for few years, no/low maintenance cost.

Kindly advise the best 1.5 ton ac for Chennai all year hot weather.

Sanjay Kumar Soni
June 2, 2015

my room size is 16 feet X 10.5 feet. Can I use 1.5 ton 5 star split Ac/window AC. Which is better

May 27, 2015

I have a 220 sq foot room (13*17) just below the roof here in Kolkata. Temperatures soar around 37-38 degrees. Which AC would be ideal for me?

Rajarshi Ghosh
June 1, 2015

Any recommendations about which brand of AC’s I should target?

May 27, 2015

Iam looking out for 1.5 ton ac best EER . Kindly suggest with brand,model, EER and price table please.Thanks

Chiranjit Pal
May 25, 2015

My room’s dimension is 10*13 (roof exposed to sunlight) at south-east corner with two 3.5*4.5 window and two door; another room is 8.5*11 (also exposed) at south with with one 3.5*4.5 window and one door , for two peoples in each room at Burdwan,WB. Need to operate at night preferably (at weekend day time). ACs will be used for 4 months 5-6 hrs at summer time. Please suggest ACs with model no. and good service at Burdwan around 25-35k. Is Blue star multi-inverter AC will be useful?